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Microalgae are a renewable and promising biomass for large-scale biofuel, food and nutrient production. However, their efficient exploitation depends on our knowledge of the cell wall composition and organization as it can limit access to high-value molecules. Here we provide an atomic-level model of the non-crystalline and water-insoluble glycoprotein-rich cell wall of Chlamydomonas reinhardtii. Using in situ solid-state and sensitivity-enhanced nuclear magnetic resonance, we reveal unprecedented details on the protein and carbohydrate composition and their nanoscale heterogeneity, as well as the presence of spatially segregated protein- and glycan-rich regions with different dynamics and hydration levels. We show that mannose-rich lower-molecular-weight proteins likely contribute to the cell wall cohesion by binding to high-molecular weight protein components, and that water provides plasticity to the cell-wall architecture. The structural insight exemplifies strategies used by nature to form cell walls devoid of cellulose or other glycan polymers., Microalgae are a renewable and promising biomass for large-scale biofuel, food and nutrient production. However, their efficient exploitation depends on our knowledge of the cell wall composition and organization as it can limit access to high-value molecules. Here we provide an atomic-level model of the non-crystalline and water-insoluble glycoprotein-rich cell wall of Chlamydomonas reinhardtii. Using in situ solid-state and sensitivity-enhanced nuclear magnetic resonance, we reveal unprecedented details on the protein and carbohydrate composition and their nanoscale heterogeneity, as well as the presence of spatially segregated protein- and glycan-rich regions with different dynamics and hydration levels. We show that mannose-rich lower-molecular-weight proteins likely contribute to the cell wall cohesion by binding to high-molecular weight protein components, and that water provides plasticity to the cell-wall architecture. The structural insight exemplifies strategies used by nature to form cell walls devoid of cellulose or other glycan polymers.

Microalgae are a renewable and promising biomass for large-scale biofuel, food and nutrient production. However, their efficient exploitation depends on our knowledge of the cell wall composition and organization as it can limit access to high-value molecules. Here we provide an atomic-level model of the non-crystalline and water-insoluble glycoprotein-rich cell wall of Chlamydomonas reinhardtii. Using in situ solid-state and sensitivity-enhanced nuclear magnetic resonance, we reveal unprecedented details on the protein and carbohydrate composition and their nanoscale heterogeneity, as well as the presence of spatially segregated protein- and glycan-rich regions with different dynamics and hydration levels. We show that mannose-rich lower-molecular-weight proteins likely contribute to the cell wall cohesion by binding to high-molecular weight protein components, and that water provides plasticity to the cell-wall architecture. The structural insight exemplifies strategies used by nature to form cell walls devoid of cellulose or other glycan polymers., Microalgae are a renewable and promising biomass for large-scale biofuel, food and nutrient production. However, their efficient exploitation depends on our knowledge of the cell wall composition and organization as it can limit access to high-value molecules. Here we provide an atomic-level model of the non-crystalline and water-insoluble glycoprotein-rich cell wall of Chlamydomonas reinhardtii. Using in situ solid-state and sensitivity-enhanced nuclear magnetic resonance, we reveal unprecedented details on the protein and carbohydrate composition and their nanoscale heterogeneity, as well as the presence of spatially segregated protein- and glycan-rich regions with different dynamics and hydration levels. We show that mannose-rich lower-molecular-weight proteins likely contribute to the cell wall cohesion by binding to high-molecular weight protein components, and that water provides plasticity to the cell-wall architecture. The structural insight exemplifies strategies used by nature to form cell walls devoid of cellulose or other glycan polymers.

Humans perceive the world through multiple senses, enabling them to create a comprehensive representation of their surroundings and to generalize information across domains. For instance, when a textual description of a scene is given, humans can mentally visualize it. In fields like robotics and Reinforcement Learning (RL), agents can also access information about the environment through multiple sensors; yet redundancy and complementarity between sensors is difficult to exploit as a source of robustness (e.g. against sensor failure) or generalization (e.g. transfer across domains). Prior research demonstrated that a robust and flexible multimodal representation can be efficiently constructed based on the cognitive science notion of a 'Global Workspace': a unique representation trained to combine information across modalities, and to broadcast its signal back to each modality. Here, we explore whether such a brain-inspired multimodal representation could be advantageous for RL agents. First, we train a 'Global Workspace' to exploit information collected about the environment via two input modalities (a visual input, or an attribute vector representing the state of the agent and/or its environment). Then, we train a RL agent policy using this frozen Global Workspace. In two distinct environments and tasks, our results reveal the model's ability to perform zero-shot cross-modal transfer between input modalities, i.e. to apply to image inputs a policy previously trained on attribute vectors (and vice-versa), without additional training or fine-tuning. Variants and ablations of the full Global Workspace (including a CLIP-like multimodal representation trained via contrastive learning) did not display the same generalization abilities., Comment: Under review in a conference

The aerospace industry can benefit from conversational agents that provide efficient solutions for safety-of-life scenarios. This industry is characterized by products and systems that require years of engineering to achieve optimal performance within complex environments. With recent advances in retrieval and language models, conversational agents can be developed to enhance the system’s question-answering capabilities. However, evaluating the added-value of such systems in the context of industrial applications, such as pilots in a cockpit, can be challenging. This article presents the design, implementation, and user evaluation of a conversational agent called Smart Librarian, which is tailored to the aerospace domain’s specific requirements to support pilots in their tasks. Our results based on a controlled user experiment with flight school students indicate that the user’s perception of the usefulness of the system in completing the search task is a good predictor of both task score and time spent. The system’s responses to the relevance of the topic is also a good predictor of task score. The perceived difficulty of the search task and its interaction with the relevance of the system’s responses to the topic also play a key role in search performance. The mixed-effects models constructed in this study had large effect sizes, demonstrating participants’ ability to assess their performance accurately. Nevertheless, user satisfaction with the system’s responses may not be a reliable predictor of user search performance. Implications for the design of conversational agents based on the domain’s specific requirements are discussed.

The aerospace industry can benefit from conversational agents that provide efficient solutions for safety-of-life scenarios. This industry is characterized by products and systems that require years of engineering to achieve optimal performance within complex environments. With recent advances in retrieval and language models, conversational agents can be developed to enhance the system’s question-answering capabilities. However, evaluating the added-value of such systems in the context of industrial applications, such as pilots in a cockpit, can be challenging. This article presents the design, implementation, and user evaluation of a conversational agent called Smart Librarian, which is tailored to the aerospace domain’s specific requirements to support pilots in their tasks. Our results based on a controlled user experiment with flight school students indicate that the user’s perception of the usefulness of the system in completing the search task is a good predictor of both task score and time spent. The system’s responses to the relevance of the topic is also a good predictor of task score. The perceived difficulty of the search task and its interaction with the relevance of the system’s responses to the topic also play a key role in search performance. The mixed-effects models constructed in this study had large effect sizes, demonstrating participants’ ability to assess their performance accurately. Nevertheless, user satisfaction with the system’s responses may not be a reliable predictor of user search performance. Implications for the design of conversational agents based on the domain’s specific requirements are discussed.

The aerospace industry can benefit from conversational agents that provide efficient solutions for safety-of-life scenarios. This industry is characterized by products and systems that require years of engineering to achieve optimal performance within complex environments. With recent advances in retrieval and language models, conversational agents can be developed to enhance the system’s question-answering capabilities. However, evaluating the added-value of such systems in the context of industrial applications, such as pilots in a cockpit, can be challenging. This article presents the design, implementation, and user evaluation of a conversational agent called Smart Librarian, which is tailored to the aerospace domain’s specific requirements to support pilots in their tasks. Our results based on a controlled user experiment with flight school students indicate that the user’s perception of the usefulness of the system in completing the search task is a good predictor of both task score and time spent. The system’s responses to the relevance of the topic is also a good predictor of task score. The perceived difficulty of the search task and its interaction with the relevance of the system’s responses to the topic also play a key role in search performance. The mixed-effects models constructed in this study had large effect sizes, demonstrating participants’ ability to assess their performance accurately. Nevertheless, user satisfaction with the system’s responses may not be a reliable predictor of user search performance. Implications for the design of conversational agents based on the domain’s specific requirements are discussed.

The aerospace industry can benefit from conversational agents that provide efficient solutions for safety-of-life scenarios. This industry is characterized by products and systems that require years of engineering to achieve optimal performance within complex environments. With recent advances in retrieval and language models, conversational agents can be developed to enhance the system’s question-answering capabilities. However, evaluating the added-value of such systems in the context of industrial applications, such as pilots in a cockpit, can be challenging. This article presents the design, implementation, and user evaluation of a conversational agent called Smart Librarian, which is tailored to the aerospace domain’s specific requirements to support pilots in their tasks. Our results based on a controlled user experiment with flight school students indicate that the user’s perception of the usefulness of the system in completing the search task is a good predictor of both task score and time spent. The system’s responses to the relevance of the topic is also a good predictor of task score. The perceived difficulty of the search task and its interaction with the relevance of the system’s responses to the topic also play a key role in search performance. The mixed-effects models constructed in this study had large effect sizes, demonstrating participants’ ability to assess their performance accurately. Nevertheless, user satisfaction with the system’s responses may not be a reliable predictor of user search performance. Implications for the design of conversational agents based on the domain’s specific requirements are discussed.

The aerospace industry can benefit from conversational agents that provide efficient solutions for safety-of-life scenarios. This industry is characterized by products and systems that require years of engineering to achieve optimal performance within complex environments. With recent advances in retrieval and language models, conversational agents can be developed to enhance the system’s question-answering capabilities. However, evaluating the added-value of such systems in the context of industrial applications, such as pilots in a cockpit, can be challenging. This article presents the design, implementation, and user evaluation of a conversational agent called Smart Librarian, which is tailored to the aerospace domain’s specific requirements to support pilots in their tasks. Our results based on a controlled user experiment with flight school students indicate that the user’s perception of the usefulness of the system in completing the search task is a good predictor of both task score and time spent. The system’s responses to the relevance of the topic is also a good predictor of task score. The perceived difficulty of the search task and its interaction with the relevance of the system’s responses to the topic also play a key role in search performance. The mixed-effects models constructed in this study had large effect sizes, demonstrating participants’ ability to assess their performance accurately. Nevertheless, user satisfaction with the system’s responses may not be a reliable predictor of user search performance. Implications for the design of conversational agents based on the domain’s specific requirements are discussed.

This work investigates the potential probiotic effect of marennine - a natural pigment produced by the diatom Haslea ostrearia - on Vibrio splendidus. These marine bacteria are often considered a threat for aquaculture; therefore, chemical antibiotics can be required to reduce bacterial outbreaks. In vivo 2H solid-state NMR was used to probe the effects of marennine on the bacterial membrane in the exponential and stationary phases. Comparisons were made with polymyxin B (PxB) - an antibiotic used in aquaculture and known to interact with Gram(−) bacteria membranes. We also investigated the effect of marennine using 31P solid-state NMR on model membranes. Our results show that marennine has little effect on phospholipid headgroups dynamics, but reduces the acyl chain fluidity. Our data suggest that the two antimicrobial agents perturb V. splendidus membranes through different mechanisms. While PxB would alter the bacterial outer and inner membranes, marennine would act through a membrane stiffening mechanism, without affecting the bilayer integrity. Our study proposes this microalgal pigment, which is harmless for humans, as a potential treatment against vibriosis. -- Keywords : Antimicrobial pigment ; Polymyxin B ; Membrane fluidity ; Model membranes ; 31P and 2H NMR ; In-cell NMR.

This work investigates the potential probiotic effect of marennine - a natural pigment produced by the diatom Haslea ostrearia - on Vibrio splendidus. These marine bacteria are often considered a threat for aquaculture; therefore, chemical antibiotics can be required to reduce bacterial outbreaks. In vivo 2H solid-state NMR was used to probe the effects of marennine on the bacterial membrane in the exponential and stationary phases. Comparisons were made with polymyxin B (PxB) - an antibiotic used in aquaculture and known to interact with Gram(−) bacteria membranes. We also investigated the effect of marennine using 31P solid-state NMR on model membranes. Our results show that marennine has little effect on phospholipid headgroups dynamics, but reduces the acyl chain fluidity. Our data suggest that the two antimicrobial agents perturb V. splendidus membranes through different mechanisms. While PxB would alter the bacterial outer and inner membranes, marennine would act through a membrane stiffening mechanism, without affecting the bilayer integrity. Our study proposes this microalgal pigment, which is harmless for humans, as a potential treatment against vibriosis. -- Keywords : Antimicrobial pigment ; Polymyxin B ; Membrane fluidity ; Model membranes ; 31P and 2H NMR ; In-cell NMR.

The aerospace industry relies on massive collections of complex and technical documents covering system descriptions, manuals or procedures. This paper presents a question answering (QA) system that would help aircraft pilots access information in this documentation by naturally interacting with the system and asking questions in natural language. After describing each module of the dialog system, we present a multi-task based approach for the QA module which enables performance improvement on a Flight Crew Operating Manual (FCOM) dataset. A method to combine scores from the retriever and the QA modules is also presented., Comment: 11 pages, 8 figures

Vibrio splendidus is a marine bacterium often considered as a threat in aquaculture hatcheries where it is responsible for mass mortality events, notably of bivalves' larvae. This bacterium is highly adapted to dynamic salty ecosystems where it has become an opportunistic and resistant species. To characterize their membranes as a first and necessary step toward studying bacterial interactions with diverse molecules, we established a labelling protocol for in vivo 2H solid-state nuclear magnetic resonance (SS-NMR) analysis of V. splendidus. 2H SS-NMR is a useful tool to study the organization and dynamics of phospholipids at the molecular level, and its application to intact bacteria is further advantageous as it allows probing acyl chains in their natural environment and study membrane interactions. In this study, we showed that V. splendidus can be labelled using deuterated palmitic acid, and demonstrated the importance of surfactant choice in the labelling protocol. Moreover, we assessed the impact of lipid deuteration on the general fitness of the bacteria, as well as the saturated-to-unsaturated fatty acid chains ratio and its impact on the membrane properties. We further characterize the evolution of V. splendidus membrane fluidity during different growth stages and relate it to fatty acid chain composition. Our results show larger membrane fluidity during the stationary growth phase compared to the exponential growth phase under labelling conditions - an information to take into account for future in vivo SS-NMR studies. Our lipid deuteration protocol optimized for V. splendidus is likely applicable other microorganisms for in vivo NMR studies. Keywords : In-cell NMR ; Deuterium ; Isotopic labelling ; Membrane fluidity ; Fatty acids ; Magic-angle spinning.

Vibrio splendidus is a marine bacterium often considered as a threat in aquaculture hatcheries where it is responsible for mass mortality events, notably of bivalves' larvae. This bacterium is highly adapted to dynamic salty ecosystems where it has become an opportunistic and resistant species. To characterize their membranes as a first and necessary step toward studying bacterial interactions with diverse molecules, we established a labelling protocol for in vivo 2H solid-state nuclear magnetic resonance (SS-NMR) analysis of V. splendidus. 2H SS-NMR is a useful tool to study the organization and dynamics of phospholipids at the molecular level, and its application to intact bacteria is further advantageous as it allows probing acyl chains in their natural environment and study membrane interactions. In this study, we showed that V. splendidus can be labelled using deuterated palmitic acid, and demonstrated the importance of surfactant choice in the labelling protocol. Moreover, we assessed the impact of lipid deuteration on the general fitness of the bacteria, as well as the saturated-to-unsaturated fatty acid chains ratio and its impact on the membrane properties. We further characterize the evolution of V. splendidus membrane fluidity during different growth stages and relate it to fatty acid chain composition. Our results show larger membrane fluidity during the stationary growth phase compared to the exponential growth phase under labelling conditions - an information to take into account for future in vivo SS-NMR studies. Our lipid deuteration protocol optimized for V. splendidus is likely applicable other microorganisms for in vivo NMR studies. Keywords : In-cell NMR ; Deuterium ; Isotopic labelling ; Membrane fluidity ; Fatty acids ; Magic-angle spinning.

Short-rotation intensive cultures (SRICs) of willows can potentially sequester carbon (C) in soil. However, there is limited information regarding the factors governing soil organic C (Corg) accumulation following afforestation. The objectives of this study were to: (i) determine whether willow leads to Corg accumulation in the topsoil (0–10 cm) two to six years after establishment in five SRICs located along a large climatic/productivity gradient in southern Quebec, and (ii) assess the influence of leaf litter decomposition and soil organic matter (OM) quality on Corg accumulation in the topsoil. Topsoil Corg concentrations and pools under SRICs were, on average, 25% greater than reference fields, and alkyls concentrations were higher under SRICs. On an annualized basis, Corg accumulation rates in the topsoil varied between 0.4 and 4.5 Mg ha−1 yr−1. Estimated annual litterfall C fluxes were in the same order of magnitude, suggesting that SRICs can accumulate Corg in the topsoil during early years due to high growth rates. Leaf litter decomposition was also related to Corg accumulation rates in the topsoil. It was positively correlated to growing season length, degree-days, and growing season average air and topsoil temperature (r > 0.70), and negatively correlated to topsoil volumetric water content (r = −0.55). Leaf litter decomposition likely occurred more quickly than that of plants in reference fields, and as it progressed, OM became more decay resistant, more stable and accumulated as Corg in the topsoil.

Short-rotation intensive cultures (SRICs) of willows can potentially sequester carbon (C) in soil. However, there is limited information regarding the factors governing soil organic C (Corg) accumulation following afforestation. The objectives of this study were to: (i) determine whether willow leads to Corg accumulation in the topsoil (0–10 cm) two to six years after establishment in five SRICs located along a large climatic/productivity gradient in southern Quebec, and (ii) assess the influence of leaf litter decomposition and soil organic matter (OM) quality on Corg accumulation in the topsoil. Topsoil Corg concentrations and pools under SRICs were, on average, 25% greater than reference fields, and alkyls concentrations were higher under SRICs. On an annualized basis, Corg accumulation rates in the topsoil varied between 0.4 and 4.5 Mg ha−1 yr−1. Estimated annual litterfall C fluxes were in the same order of magnitude, suggesting that SRICs can accumulate Corg in the topsoil during early years due to high growth rates. Leaf litter decomposition was also related to Corg accumulation rates in the topsoil. It was positively correlated to growing season length, degree-days, and growing season average air and topsoil temperature (r > 0.70), and negatively correlated to topsoil volumetric water content (r = −0.55). Leaf litter decomposition likely occurred more quickly than that of plants in reference fields, and as it progressed, OM became more decay resistant, more stable and accumulated as Corg in the topsoil.

This research is focus in the Designing of a Monitoring Unit of Technology to manage knowledge in the development of free software information technologies at the National Center of Information Technologies (CNTI), supported by Sánchez (2011), Castellanos (2005), Escorsa, Ortiz and Maspons (2002), as theoretical authors. This research is classify as a descriptive research. The design as non-experimental field, in the form of feasible project, based on an assessment of the substantive area at CNTI this is why their sample consisted of: Executive Director, Office of Process Modeling, Office of Strategic Planning, Management State Care, Technology Management Training, Project Management Division, Technology and Management-Operations. The Reporting units or sources were established by 14 subjects serving as director, manager or coordinator, with two (2) or more years of experience in managing external information, a questionnaire for data collection was used. The questionnaire has 30 closed questions on a interval measurement scale, the questionnaire was validated by the judgment of three experts in the area of interest. The reliability of the questionnaire was established through a pilot test applied to 3 subjects in the areas of study, using the test / retest method for calculating the coefficient of Alpha Cronbach resulting in a value of 0.928, which is regarded as highly reliable. It is important to note that the data collected was treated through the use of percentages and frequencies, represented in bar graphs through the used of a spreadsheet. It was concluded that the Monitoring of Technology can meet the needs of users in the processes for making decisions based on the information available outside the institution; under a new approach to model knowledge management.Keywords: technology watch, competitive intelligence, knowledge management., En esta investigación se propuso el Diseño de la Unidad de Monitoreo Tecnológico para gestionar el conocimiento en el desarrollo de las tecnologías de información libres en el Centro Nacional de Tecnologías de Información (CNTI), sustentada en Sánchez (2011), Castellanos (2005), Escorsa, Ortiz y Maspons (2002), así como autores teóricos. La investigación se tipificó como descriptiva. El diseño como no experimental de campo, bajo la modalidad de proyecto factible, sustentado en un diagnóstico del área sustantiva del CNTI, es por ello, su muestra estuvo constituida por: Dirección Ejecutiva, Oficina de Modelado de Procesos, Oficina de Planificación Estratégica, Gerencia de Atención al Estado, Gerencia de Formación Tecnológica, Gerencia de Gestión de Proyectos, y la Gerencia Tecnología-Operaciones. Las unidades informantes las conformaron 14 sujetos que desempeñan funciones de director, gerente o coordinador, con dos (2) o más años de experiencia en la gestión de información externa. Se empleó la encuesta como técnica para la recolección de los datos el cuestionario con preguntas cerradas, bajo escala de medición de intervalos, con 30 preguntas; instrumento que fue validado el juicio de tres expertos. La confiabilidad del instrumento se estableció a través de una prueba piloto aplicada a 3 sujetos dentro de las áreas de estudio, utilizando el método test/retest, para el cálculo del coeficiente de Alfa Cronbach se obtuvo un valor de 0,928, el cual se considera altamente confiable. Es importante señalar que los datos recolectados fueron tratados a través del uso de porcentajes y frecuencias, representados en gráficos de barras, mediante el uso de la hoja de cálculo. Se concluyó que el Monitoreo Tecnológico puede atender las necesidades de los usuarios en los procesos para la toma de decisiones con base a la información disponible en el exterior de la institución; bajo un nuevo enfoque en su modelo de gestión del conocimiento. Palabras Claves: vigilancia tecnológica, intel

This research is focus in the Designing of a Monitoring Unit of Technology to manage knowledge in the development of free software information technologies at the National Center of Information Technologies (CNTI), supported by Sánchez (2011), Castellanos (2005), Escorsa, Ortiz and Maspons (2002), as theoretical authors. This research is classify as a descriptive research. The design as non-experimental field, in the form of feasible project, based on an assessment of the substantive area at CNTI this is why their sample consisted of: Executive Director, Office of Process Modeling, Office of Strategic Planning, Management State Care, Technology Management Training, Project Management Division, Technology and Management-Operations. The Reporting units or sources were established by 14 subjects serving as director, manager or coordinator, with two (2) or more years of experience in managing external information, a questionnaire for data collection was used. The questionnaire has 30 closed questions on a interval measurement scale, the questionnaire was validated by the judgment of three experts in the area of interest. The reliability of the questionnaire was established through a pilot test applied to 3 subjects in the areas of study, using the test / retest method for calculating the coefficient of Alpha Cronbach resulting in a value of 0.928, which is regarded as highly reliable. It is important to note that the data collected was treated through the use of percentages and frequencies, represented in bar graphs through the used of a spreadsheet. It was concluded that the Monitoring of Technology can meet the needs of users in the processes for making decisions based on the information available outside the institution; under a new approach to model knowledge management.Keywords: technology watch, competitive intelligence, knowledge management., En esta investigación se propuso el Diseño de la Unidad de Monitoreo Tecnológico para gestionar el conocimiento en el desarrollo de las tecnologías de información libres en el Centro Nacional de Tecnologías de Información (CNTI), sustentada en Sánchez (2011), Castellanos (2005), Escorsa, Ortiz y Maspons (2002), así como autores teóricos. La investigación se tipificó como descriptiva. El diseño como no experimental de campo, bajo la modalidad de proyecto factible, sustentado en un diagnóstico del área sustantiva del CNTI, es por ello, su muestra estuvo constituida por: Dirección Ejecutiva, Oficina de Modelado de Procesos, Oficina de Planificación Estratégica, Gerencia de Atención al Estado, Gerencia de Formación Tecnológica, Gerencia de Gestión de Proyectos, y la Gerencia Tecnología-Operaciones. Las unidades informantes las conformaron 14 sujetos que desempeñan funciones de director, gerente o coordinador, con dos (2) o más años de experiencia en la gestión de información externa. Se empleó la encuesta como técnica para la recolección de los datos el cuestionario con preguntas cerradas, bajo escala de medición de intervalos, con 30 preguntas; instrumento que fue validado el juicio de tres expertos. La confiabilidad del instrumento se estableció a través de una prueba piloto aplicada a 3 sujetos dentro de las áreas de estudio, utilizando el método test/retest, para el cálculo del coeficiente de Alfa Cronbach se obtuvo un valor de 0,928, el cual se considera altamente confiable. Es importante señalar que los datos recolectados fueron tratados a través del uso de porcentajes y frecuencias, representados en gráficos de barras, mediante el uso de la hoja de cálculo. Se concluyó que el Monitoreo Tecnológico puede atender las necesidades de los usuarios en los procesos para la toma de decisiones con base a la información disponible en el exterior de la institución; bajo un nuevo enfoque en su modelo de gestión del conocimiento. Palabras Claves: vigilancia tecnológica, intel

Short-rotation intensive cultures (SRICs) of willows can potentially sequester carbon (C) in soil. However, there is limited information regarding the factors governing soil organic C (Corg) accumulation following afforestation. The objectives of this study were to: (i) determine whether willow leads to Corg accumulation in the topsoil (0–10 cm) two to six years after establishment in five SRICs located along a large climatic/productivity gradient in southern Quebec, and (ii) assess the influence of leaf litter decomposition and soil organic matter (OM) quality on Corg accumulation in the topsoil. Topsoil Corg concentrations and pools under SRICs were, on average, 25% greater than reference fields, and alkyls concentrations were higher under SRICs. On an annualized basis, Corg accumulation rates in the topsoil varied between 0.4 and 4.5 Mg ha−1 yr−1. Estimated annual litterfall C fluxes were in the same order of magnitude, suggesting that SRICs can accumulate Corg in the topsoil during early years due to high growth rates. Leaf litter decomposition was also related to Corg accumulation rates in the topsoil. It was positively correlated to growing season length, degree-days, and growing season average air and topsoil temperature (r > 0.70), and negatively correlated to topsoil volumetric water content (r = −0.55). Leaf litter decomposition likely occurred more quickly than that of plants in reference fields, and as it progressed, OM became more decay resistant, more stable and accumulated as Corg in the topsoil.

Exhaustive formal verification for systems of systems (SoS) is impractical and cannot be applied on a large scale. In this paper we propose to use statistical model checking for efficient verification of SoS. We address three relevant aspects for systems of systems: 1) the model of the SoS, which includes stochastic aspects; 2) the formalization of the SoS requirements in the form of contracts; 3) the tool-chain to support statistical model checking for SoS. We adapt the SMC technique for application to heterogeneous SoS. We extend the UPDM/SysML specification language to express the SoS requirements that the implemented strategies over the SoS must satisfy. The requirements are specified with a new contract language specifically designed for SoS, targeting a high-level English- pattern language, but relying on an accurate semantics given by the standard temporal logics. The contracts are verified against the UPDM/SysML specification using the Statistical Model Checker (SMC) PLASMA combined with the simulation engine DESYRE, which integrates heterogeneous behavioral models through the functional mock-up interface (FMI) standard. The tool-chain allows computing an estimation of the satisfiability of the contracts by the SoS. The results help the system architect to trade-off different solutions to guide the evolution of the SoS., Comment: In Proceedings AiSoS 2013, arXiv:1311.3195

This paper presents some of the results of the first year of DANSE, one of the first EU IP projects dedicated to SoS. Concretely, we offer a tool chain that allows to specify SoS and SoS requirements at high level, and analyse them using powerful toolsets coming from the formal verification area. At the high level, we use UPDM, the system model provided by the british army as well as a new type of contract based on behavioral patterns. At low level, we rely on a powerful simulation toolset combined with recent advances from the area of statistical model checking. The approach has been applied to a case study developed at EADS Innovation Works., Comment: In Proceedings AiSoS 2013, arXiv:1311.3195